Hi, My heater supply is AC which is fine but I would like to use the same tap of the transformer to provide a rectified DC signal for channel switching etc.

I was going to rectify after the input valve at the end of the AC chain but unfortunately this is on the opposite end of the chassis to where I need it. Would it make any difference for better or for worse simply taking another two wires off the beginning of the chain which is attached to a filament lamp and rectifying there?
Thanks

Your idea seems fine to me. Taking some extra power from close to the source is the correct way of doing it anyway. A small bridge rectifier, or full wave depending on your configuration, and a single filter cap should serve well. Just remember common sense things like keeping AC wires away from signal lines and twisting them close to the chassis if there is length involved.

Victor

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